**11. Aspects of MRI after CAS**

There were no new areas of cerebral infarction after CAS in the analysis of conventional MRI sequences.

A comparison between the MRI diffusion sequences acquired before and after angioplasty showed 59 NF of restriction compatible with cerebral ischemia, which were distributed in 18/36 (50%) patients (Figures 5 and 6). The average NF in the 36 patients was 1.6 NF/patient (Table 5), and the diameter varied between 1 and 25 mm.


1 Two patients were excluded from the analysis of laterality

**10. Imaging results**

**10.1. Aspects of MRI before the CAS**

164 Carotid Artery Disease - From Bench to Bedside and Beyond

**Table 4.** MRI data before CAS (n = 36)

**11. Aspects of MRI after CAS**

sequences.

stenosis.

The preliminary MRI study before CAS showed six restriction foci in diffusion in four (11.11%)

Among the restriction foci in DWI before CAS, five out of six (83.33%) were ipsilateral to the carotid artery for CAS, and only one focus was not ipsilateral to the carotid that was treated (cerebellum). All hypersignal foci in DWI before CAS occurred in patients with symptomatic

**Figure 4.** Patient number 7, male, 60 years old, underwent angioplasty of the left carotid artery. Restriction foci in DWI in the MRI scan before CAS (A). Manifestation found in 11.11% of patients. No NF were observed after CAS (B)

There were no new areas of cerebral infarction after CAS in the analysis of conventional MRI

**n (%) patients**

patients (Table 4 and Figure 4). These foci were not recorded as NF after CAS.

Infarctions in T2 23 (63.9) Foci of restriction in DWI (1ª MR) 4 (11.1)

**Table 5.** Characteristics of new foci (NF) of hypersignal in DWI after angioplasty of the carotid artery

**Figure 5.** Patient number 9, 59 years old, underwent right CAS. DWI before CAS (A) without images of restriction. After CAS (B): ipsilateral NF (including primary motor rotation) and contralateral NF. Asymptomatic patient.

**Presentation of NF per patient n of NF n of pt Average**

TOTAL 59 18

IP pure + intersection (IP+CL in the same patient)=11 patients=32.35%

**Table 8.** Distribution of NF based on laterality per patient (n=34 patients1)

IP pure 14 NF 2.80

Bilateral 38 NF 6.33

1 Two patients were excluded from the analysis of laterality.

1 Two patients were excluded from the analysis of laterality.

IP pure: patients with only ipsilateral NF; CL pure: patients with only contralateral NF

**Laterality by patient n of NF Average2 p**

CL pure 5 NF 1.00 0.053

**Table 9.** Number and average of NF according to laterality per patient (n=34 patients1)

IP pure: patients with only ipsilateral NF; CL pure: patients with only contralateral NF; Bilateral: patients with both

**Table 7.** Distribution of NF (single or multiple)

pt – patient

Mann-Whitney U test

No statistical test

ipsilateral and contralateral NF

<sup>2</sup> NF per case Kruskal-Wallis test

Single NF (1 nf/ pt) 9 9 1.00 0.00

**Laterality Number of patients % of patients**

IP pure 5 14.71 CL pure 5 14.71 Intersection (IP+CL in the same patient) 6 17.65

Multiple NF (≥2 nf/pt) 50 9 5.56 3.43 <0,001

**(NF/pt)**

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**SD p**

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**Figure 6.** Patient 27, male, 73 years old with right carotid artery occlusion and stenosis of the left carotid artery esti‐ mated at 70% by DSA (not shown). Before CAS: T2 sequence (A) shows old infarction in the territory of the right MCA and diffusion sequence (C) without recent ischemia foci. The patient underwent DSA of both common carotid arteries and CAS of the left. In the MRI study, the T2 sequence was unchanged after CAS (B) and the DWI sequence showed NF in the head of the caudate nucleus to the right (D)


CL – NF contralateral to the area for CAS; IP – NF ipsilateral to the area for CAS

1 Two patients were excluded from the analysis of laterality.

2 NF/patients

Wilcoxon test

**Table 6.** Number and average of NF by laterality (n=16 patients1)


**Table 7.** Distribution of NF (single or multiple)


IP pure + intersection (IP+CL in the same patient)=11 patients=32.35%

IP pure: patients with only ipsilateral NF; CL pure: patients with only contralateral NF

1 Two patients were excluded from the analysis of laterality.

No statistical test

**Figure 6.** Patient 27, male, 73 years old with right carotid artery occlusion and stenosis of the left carotid artery esti‐ mated at 70% by DSA (not shown). Before CAS: T2 sequence (A) shows old infarction in the territory of the right MCA and diffusion sequence (C) without recent ischemia foci. The patient underwent DSA of both common carotid arteries and CAS of the left. In the MRI study, the T2 sequence was unchanged after CAS (B) and the DWI sequence showed NF

**Laterality of NF % of NF n of NF Average2 P**

CL 22.81 13 0.81 0.063

IP 77.19 44 2.75

Total 100.00 57 3.56

CL – NF contralateral to the area for CAS; IP – NF ipsilateral to the area for CAS

1 Two patients were excluded from the analysis of laterality.

**Table 6.** Number and average of NF by laterality (n=16 patients1)

2 NF/patients Wilcoxon test

in the head of the caudate nucleus to the right (D)

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**Table 8.** Distribution of NF based on laterality per patient (n=34 patients1)


IP pure: patients with only ipsilateral NF; CL pure: patients with only contralateral NF; Bilateral: patients with both ipsilateral and contralateral NF

1 Two patients were excluded from the analysis of laterality.

<sup>2</sup> NF per case

Kruskal-Wallis test

**Table 9.** Number and average of NF according to laterality per patient (n=34 patients1)


**Risk factors**

ease; HBP: high blood pressure Logistic regression analysis

1 Patient

Chi-squared test

Mann-Whitney U test

after CAS

**NF**

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**N % n %** TIA 8 44.44 9 50.00 0.800 ICVA 4 22.22 7 38.89 0.612 ICVA or TIA 12 66.67 14 77.78 0.845 ARR 2 11.11 2 11.11 1.000 COL 8 44.44 4 22.22 0.164 COR 4 22.22 5 27.78 0.701 DM 5 27.78 7 38.89 0.481 PVD 10 55.56 9 50.00 0.738 HBP 15 83.33 17 94.44 0.311

TIA: transient ischemic attack; ICVA: ischemic cerebral vascular accident; TIA or ICVA: cases with at least one ischemic condition; ARR: arrhythmia; COL: hypercholesterolemia; COR: ischemic coronary artery disease; DM: diabetes; PVD: peripheral vascular dis‐

**Table 13.** Distribution of risk factors in relation to the appearance of NF after CAS

**Table 14.** Occurrence of NF based on the presence of symptoms before CAS

Asymptomatic 11 18.6

TOTAL 59 100.0

**Patients n of pt1 % pt n of pt % pt** Asymptomatic (n=9) 7 77.8% 2 22.2%

**Clinical status of the patient before CAS n of NF % of NF p**

Symptomatic 48 81.4 0.263

**Table 15.** Correlation between the presence of carotid disease symptoms before the procedure and the number of NF

Symptomatic (n=27) 11 40.7% 16 59.26% 0.121

**No Yes p**

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169

**NF**

**No Yes p**

**Table 10.** Average and standard deviation of age in the groups with and without NF in the DWI after CAS.


**Table 11.** Distribution of age, gender, and side of the carotid artery treated based on the appearance of NF in the DWI after CAS.


1 Risk factors for atherosclerosis/ICVA

2 Standard deviation for risk factors

3 Patient

Mann-Whitney U test

**Table 12.** Correlation of all risk factors with NF after CAS


TIA: transient ischemic attack; ICVA: ischemic cerebral vascular accident; TIA or ICVA: cases with at least one ischemic condition; ARR: arrhythmia; COL: hypercholesterolemia; COR: ischemic coronary artery disease; DM: diabetes; PVD: peripheral vascular dis‐ ease; HBP: high blood pressure

Logistic regression analysis

**NF after CAS Average age (years) SD p**

<75 8 44.4 7 38.9

TOTAL 18 100.0 18 100.0

Male 15 83.3 10 55.6

TOTAL 18 100.0 18 100.0

Right 8 44.4 7 38.9

TOTAL 18 100.0 18 100.0

Risk factors1(n=116) 60 1.75 56 1.18

With NF 72.33 7.75 0.855

**Table 10.** Average and standard deviation of age in the groups with and without NF in the DWI after CAS.

**No Yes n % n %**

≥75 10 55.6 11 61.1 0.855

Female 3 16.7 8 44.4 0.080

Left 10 55.6 11 61.1 0.735

**Table 11.** Distribution of age, gender, and side of the carotid artery treated based on the appearance of NF in the DWI

**n factors SD2 n factors SD2**

Patients (n=36) 18 3.33 18 3.11 0.743

**NF**

n of patients Average (NF/pt3) n patients Average (NF/pt3)

**Yes No p**

**NF**

**p**

Without NF 71.83 9.03

168 Carotid Artery Disease - From Bench to Bedside and Beyond

Mann-Whitney U test

**Factor**

AGE (years)

GENDER

CAROTID ARTERY

after CAS.

3 Patient

Mann-Whitney U test

Logistic regression analysis

1 Risk factors for atherosclerosis/ICVA 2 Standard deviation for risk factors

**Table 12.** Correlation of all risk factors with NF after CAS

**Table 13.** Distribution of risk factors in relation to the appearance of NF after CAS


1 Patient

Chi-squared test

**Table 14.** Occurrence of NF based on the presence of symptoms before CAS


Mann-Whitney U test

**Table 15.** Correlation between the presence of carotid disease symptoms before the procedure and the number of NF after CAS


One patient (Number 19) showed one NF in the cerebellum after angioplasty of the left carotid artery (Figure 7). Forty days later, the same patient was admitted for an angioplasty of the right carotid artery. Another MRI was performed at this opportunity (not as part of the research protocol), and it did not show diffusion lesions in the infarct area in T2 or in the enhancement,

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**NF**

**Occlusion of contralateral carotid artery**

**N % N %** Ulcers 7 38.89 7 38.89 1.000

**N % n %**

No 4 22.22 14 77.77 0.674

Yes 3 16.66 15 83.33

**Table 20.** Distribution of NF according to the presence of contralateral carotid occlusion.

**No Yes p**

**Yes No p**

which is common for subacute cerebral infarctions.

**12. Aspects of angiography and angioplasty**

Yes 18 73.83

**Table 19.** Presence of ulcers and appearance of NF after CAS

Mann-Whitney U test

Logistic regression analysis

**NF**

Chi-squared test

**NF N Average P**

**Table 18.** Average degree of stenosis in the groups with and without NF after CAS

No 18 78.78 0.239

1 Patient

2 Percentage of patients in the group with NF (n=18)

Logistic regression analysis

**Table 16.** Distribution of NF according to the presence of previous cerebral infarct (in T2) in the first MRI


1 Percentage related to the complete NF group (n=59)

2 Number of patients with cerebral infarct images on the initial MRI

3 NF/patient

4 Standard deviation

Mann-Whitney U test

**Table 17.** Distribution of the number of NF (after CAS) based on the presence of previous cerebral infarcts in T2 in the first MRI

**Figure 7.** Patient number 19, 81 years old with bilateral stenosis in the carotid arteries. A DSA was performed in the aortic arch, common carotid arteries, left subclavian artery, and brachiocephalic trunk before the CAS of the left caro‐ tid artery. Diffusion study before the DSA and angioplasty (A). After DSA and CAS, an NF was identified in the DWI in the left hemisphere of the cerebellum (B). A new MRI performed 40 days after the CAS (not as part of the study proto‐ col) showed the absence of lesions in the DWI (C) and in T2 (not shown).

One patient (Number 19) showed one NF in the cerebellum after angioplasty of the left carotid artery (Figure 7). Forty days later, the same patient was admitted for an angioplasty of the right carotid artery. Another MRI was performed at this opportunity (not as part of the research protocol), and it did not show diffusion lesions in the infarct area in T2 or in the enhancement, which is common for subacute cerebral infarctions.
